In the aforementioned area, we are familiar with the process of machining pre-shaped panels by electro-erosion to non-developable shapes. Such machining involves masking of the zones that are not to be treated, and then immersion in baths of electrolytic solutions. Thus, effectively, this process allows a localised machining of panels of general non-developable shape, but nevertheless has two major drawbacks.
To begin with, machining by electro-erosion constitutes a significant source of discharges to be processed, to the extent that firstly it is necessary at the end of the machining process to clean the panels by removal of the masking elements and then rinsing followed by recycling of the cleaning solutions as well as of the different electrolytic baths used.
Another disadvantage of machining by electro-erosion concerns the impossibility, with this process, of effecting a machining process involving different areas of depth in a single operation.
In the light of the above disadvantages, and in particular of the cost of processing the polluting discharges from the installations used for machining by electro-erosion, a proposal was put forward for machining by the removal of material from panels of concave or convex or indeed complex shape.
To this end, patent U.S. Pat. No. 5,163,793 proposed the creation of a machining installation that includes a sort of mattress of hydraulic jacks, fitted at their top ends with gripping device mounted on a swivel. The device also includes, on top of the mattress of jacks, a portico which is mobile in horizontal translation and which carries a machining head.
To the extent that each jack is individually adjustable in height, it is thus possible to achieve the securing of panels that are of warped or complex shapes.
It appears however that although such a device actually allowed one to effect machining by the removal of materials from panels with non-developable warped or complex shapes, it could not be used to perform high-precision machining, particularly because of its inability to guarantee adequately rigid securing of the panel to be machined.
Thus, the need has arisen for a new machining process, and for a device for the implementation of this machining process that allows one to perform a variety of machining operations and, in particular, machining by the removal of material, while still providing better working accuracy than the processes and devices of previous designs, and also allowing a significant reduction in the polluting discharges.